System for authenticating self-authenticating documents

Abstract

System for reading a self-authenticating document having machine-readable data including critical document data, digital signature data and a public key certificate. At a point of purchase or financial institution, a personal identification unit receives a personal identification number (PIN) from a presenter of a self-authenticating document, and an image scanning and processing system reads the self-authenticating document, retrieves the machine-readable data, and assembles an authenticatable data string from the critical document data and the received PIN. A parsing system parses the machine-readable data to obtain the digital signature data and the public key certificate. A validating system certifies the public key certificate to obtain an authentic public key and applies the authentic public key to the digital signature data in order to for validate the authenticatable data string. The self-authenticating document is authenticated if the authenticatable data string is validated.

Description

FIELD OF THE INVENTION The present invention generally relates to authentication of value documents. More particularly, the invention relates to a method and system for authenticating personal checks and commercial checks, as well as other personal documents and commercial value documents, wherein the data in these documents is unencrypted but secured through a digital signature. BACKGROUND OF THE INVENTION Printed documents of any kind are becoming substantially easier to forge as technology advances. Personal and business checks are no exception. For example, enhanced and inexpensively available home desktop publishing technology now widely available makes forging checks easier than ever. In addition, check processing is rapidly evolving. To reduce the costs of processing personal checks tendered for payment at a point of sale, banks, electronic fund transfer networks, and merchants seek new, more efficient methods for processing personal checks. For example, one new check proc...

AI Technical Summary

Benefits of technology

In a first aspect of a preferred embodiment of the invention, a method for printing authentication information on a value document is provided. The method includes the step of generating a first digital signature based on a critical data string and a second digital signature based on an authenticatable data string and a private key. The method further includes the step of obtaining a public key certificate from a certifying authority. According to one aspect of the present invention, the first digital signature, second digital signature and the public key certificate are then fixed to the document. Fixing security data to the document allows a significant reduction in the costs associated with authentication. Furthermore, reliability is improved due to elimination of the need for additional devices, cards etc.

In a second aspect of a preferred embodiment of the invention, a method for authenticating a personal value document is provided. The method includes the step of assembling an authenticatable data string based on machine-readable critical document data contained on the document and a personal identification number (PIN) of a user. Machine-readable security data is retrieved from the document, where the security data includes a public key, its certificate, and a second digital signature. The method further provides for validating the digital signature based on the public key and the authenticatable data string. Retrieving the security data from the document allows a simplified approach to authentication that does not require encryption or additional devices.

In a fourth aspect of a preferred embodiment of the invention, a payment system for verifying a check at a point of presentment includes a check reading system with an image scanner system, a data entry PIN pad, a parsing module, and a validation module. The PIN pad allows the entry of a user PIN and the document reader with an image scanner system allows the retrieval of machine-readable critical document data and machine-readable security data from the document, where the data processing system assembles an authenticatable data string based on the critical document data and the user PIN. The parsing module extracts a public key and its certificate and a digital signature from the security data. The validation module validates the digital signature based on the public key and the authenticatable data string.

Problems solved by technology

Problematically, the use of encryption and encryption smart cards as specified in this approach would likely require export control review by appropriate United States federal agencies before products based on this approach could cross an international boundary.

This form of encryption key management is expensive and may be no more secure than the smart cards themselves.

Images